Enclosed liquid pump



E. J. WEBSTER 3,053,194

ENCLOSED LIQUID PUMP 3 Sheets-Sheet 1 Sept. 11, 1962 Filed Nov. 25, 1960 :5 E v Q WWJIIII M lull".

Sept, 11, 1962 E. J. WEBSTER ENCLOSED LIQUID PUMP Filed Nov. 25, 1960 3 Sheets-Sheet 2 'UJIIIII fizazzfar Sept. 11, 1962 E. J. WEBSTER 3,053,194

ENCLOSED LIQUID PUMP Filed Nov. 25, 1960 5 Sheets-Sheet 3 fig- \5 1 n"! r-l I, I

$353,194 Patented Sept. 11, 1962 Iowa Filed Nov. 25, 1969, Ser. No. 71,725 7 Claims. (Cl. 103153) This invention relates to improvements in an enclosed liquid pump, and more particularly to an opposed double cylinder double acting piston pump highly desirable for the continuous supply of a liquid under pressure, although the pump Will have other uses and purposes as will be apparent to one skilled in the art.

By way of example, and not by way of limitation, the instant invention is highly desirable for use with a mobile power sprayer of either the cart or skid type for either manual or vehicle propulsion, the pump being readily mounted on the tank of the spraying device.

In the past, many and various types of liquid pumps have been used for spraying apparatus and other purposes, but have not been desirably economical especially when sold as an operable part of a unitary structure requiring the offices of a pump, the pump unit itself adding materially to the cost of the entire assembly and where the entire operating assembly is of the character of an agricultural spraying device, economy is an essential. Furthermore, pumps of the same general character heretofore knoWn were most frequently objectionably large in size for any given capacity, had the inlet and outlet ports disposed in awkward locations diilicult of access and the making of proper connections thereto, were not capable of embodying an oil bath splash type of lubrication at an economical price, were not as durable as desired and diflicult to repair particularly in regard to the cylinder and piston arrangements, were objectionably heavy, were not capable of handling many corrosive chemicals, and required a special construction for each different type of drive connection or power source, and were frequently objectionable for other reasons that will be apparent later herein.

With the foregoing in mind, it is an object of this invention to provide an economical, high capacity, and small size liquid pump.

Another object of the invention is the provision of a simple form of liquid pump extremely simple in construction whereby the pump may be assembled during manufacture in a ready and economical manner, and easily dismantled for repairs or examination, the structure embodying many less parts than pumps of similar character heretofore made.

Also an object of this invention is the provision of an opposed cylinder double acting piston type liquid pump having the inlet and outlet ports both located at the top of the pump casing in a position for reading access for the connection of liquid lines thereto.

A further feature of the invention resides in the provision of a pump embodying a casing having parallel passages therein along the top thereof for both incoming and outgoing liquid.

It is also a feature of this invention to provide a double acting piston type liquid pump having a novel valve plate arrangement easily mounted in position and held in place by the attachment of the casing heads to the casing or body itself.

It is also an object of this invention to provide a small size, high capacity liquid pump which may readily have the crankshaft thereof connected to an internal combustion or electric engine, directly from the gear reduction unit or by belt or chain drive, or may be connected to the power take-olf of a motorized vehicle with the use of a commonly known form of adaptor, no individual arrangement for each type of connection being necessary.

It is a further feature of the invention to provide an economical high capacity liquid pump utilizing an opposed double cylinder unit and having an oil bath splash type central lubrication system.

Still a further feature of the invention resides in the provision of a liquid pump having cylinder sleeves lined to resist corrosive chemicals as well as function as a guide for the pistons, thereby eliminating separate piston guides heretofore commonly used.

While some of the more salient features, characteristics and advantages of the instant invention have been above pointed out, others will become apparent from the following disclosures, taken in conjunction with the accompanying drawings, in which:

FIGURE 1 is a side view of a pump embodying principles of the instant invention, with most of the casing structure broken away and the interior illustrated in vertical section;

FIGURE 2 is a plan view of the structure of FIG- URE l with the central portion of the casing broken away to show the crankshaft and piston assembly in plan section;

FIGURE 3 is an end view of the pump taken from the right-hand side of FIGURE 1 with both the casing head and valve plate broken away to illustrate the passageways in the body or casing; and

FIGURE 4 is an end elevational View of a valve plate itself, illustrating the mounting of the valves thereon.

As shown on the drawings:

The illustrated embodiment of the instant invention comprises a pump body or casing 1 which is preferably a unitary casting of aluminum or equivalent lightweight metal for the purpose of overall lightness in the resultant pump. The casing 1 is provided with an inlet port 2 and an outlet port 3 in the top thereof, these ports communicating through the casing with parallel separated channels or passages 4 and 5 respectively and each of these passages opens through each end of the casing 1. The passage 5 is enlarged interi-orly at each end as indicated at '6 in FIGURES 1 and 3, while such enlargement is not essential for the intake passage 4 because of the outside disposition of the valves controlling flow through that passage.

The casing 1 has a relatively large transverse central opening 7 therethrough as seen in FIGURES 1 and 2 to accommodate a crankshaft assembly to be later described. At the ends thereof the casing 1 is provided with opposed cylinders 8 and 9 opening through the respective end of the casing and communicating with the opening 7 inside the casing. On the underside or anywhere else that may be convenient, the casing may be provided with suitable mounting lugs 10-10.

Each of the cylinders 8 and 9 is provided interiorly with a sleeve 11 having a porcelain lining 12, and which sleeve is sealed against leakage by means of a suitable resilient O-ring 13. Each sleeve is preferably a section of seamless steel tubing.

With reference more particularly to FIGURES 2 and 3, it will be seen that at each side of the casing l the central opening 7 is closed by a cover plate 14 having a'suitable bearing housing formation 15 integral therewith, the cover plate being secured to the casing by cap screws 16 or in an equivalent manner. Of course, a suitable gasket is disposed between the cover plate and casing as indicated at 17 in FIGURE 3. Each bearing housing formation 15 encloses a suitable bearing assembly 18 for the opposite ends of a crankshaft 19 having an integral offset crank pin 20' disposed between the cylinders 8 and 9 of the casing 1.

Opposed pistons 21 and 22 reciprocable in the cylinders 8 and 9 respectively are actuated simultaneously by the crankshaft 19. Each of these pistons is provided with a ventical base portion 23 as seen best in FIGURE 1, and this portion is extended laterally at the top and bottom thereof as seen at 24 in FIGURE 2. Between the vertical portions of the pistons 211 and 22 is a twopiece self-lubricating bearing 25 for .the crank pin 20 of the shaft 19. The lateral extensions 24 of the pistons are tied together on each side by connecting plates 2 6-26, suitably apertured to accommodate the crankshaft, and held in place by socket headed cap screws 27 or in an equivalent manner.

The head end of each piston which projects into the respective cylinder 8 or 9 is enclosed by a plastic skirt 28 which may satisfactorily be made of nylon, and outside of this skirt is the usual packing cup 29 of leather or equivalent material, both the skirt and cup being held in place on the piston by a piston head bolt 30.

As seen in FIGURE 2, an oil cup 31 is provided which communicates through one of the cover plates 14 with the opening or chamber 7 inside the casing, and this opening 7 may be filled with lubricant through the cup 31 so that oil bath splash type central lubrication is provided for the crankshaft and piston assembly.

Each end of the casing 1 is closed by a cup shaped casing head 32 held in place by cap screws 33 extending into the casing 1, or by equivalent means. Thus, each casing head provides an interior chamber 34 which establishes communication between the respective cylinder and the adjacent ends of the intake and discharge passages 4 and 5.

Between each casing head 32 and the respective end of =the casing a valve plate 35 is mounted, there being an inner head gasket 36 between the casing 1 and the valve plate, and an outer head gasket 37 between the valve plate and the adjacent casing head. The valve plate is held in position by a single cap screw 38, FIGURE 1, passing through a suitable aperture 39 in the valve plate, FIGURE 4, and by means of the aforesaid cap screws 33 which hold the casing head in place passing through suitable apertures 40 in the valve plate. This valve plate, which is preferably made of stainless steel, is provided with an opening 41 opposite the end of the respective cylinder 8 or 9, and with an opening 42 defined by an ofiset valve seat 43 opposite the adjacent end of the discharge passage 5. On the inner side of the plate within the enlarged portion 6 of the passage a skeleton valve cage 44- formed by a pair of crossed legs, the ends of which are spot welded or equivalently secured to the valve plate is mounted over the opening -42. Inside that skeleton cage is a compression spring 45 which urges a flat valve 46 against the valve seat 43, to normally maintain the opening 42 closed.

A similar valve cage 47, spring 48, and valve 49 is mounted on the outside of the valve plate Within the chamber 34 of the casing head closing an opening in the plate opposite the end of the intake passage 4. The suction of the respective piston on the intake stroke overcomes the action of the spring 48 and opens the poppet valve 49 to admit liquid into the chamber 34 and cylinder 8 or 9, and likewise the outward force of the piston on a pumping stroke overcomes the action of the spring 45 to open the poppet valve 46 and eject liquid through the passage 5 and discharge port 3.

It is to be understood that a pipeline leading from a supply of liquid may be connected .to the intake port 2 in any well known manner, and a discharge pipeline similarly connected to the port 3. As the crankshaft rotates, the pistons move in unison, and while the piston 21 forces liquid through the discharge passage 5 and out the port 3, the piston 22 draws in liquid through the port 2 and intake passage 4, during the first half revolution of the crankshaft, and during the second half revolution of the crankshaft the pistons act in the opposite manner, so that a complete revolution of the crankshaft provides both an intake and discharge stroke for each piston, and the pumping action is substantially continuous.

The structure of the instant pump provides many advantages. It will be noted that identical parts are utilized at each end of the casing 1 and identical parts are utilized at each side of the casing l. The entire pump is extremely light in Weight, small in size, and yet embodies an oil bath splash type central lubrication system.

The porcelain lined steel cylinder sleeves are positioned against a shoulder in the casing 1, sealed by the aforesaid O-ring 13 and held firmly in position by the valve plate 35 and casing head bolts, The porcelain lined cylinder sleeves permit the pumping of chemicals and agricultural spray mixtures without damage or corrosive action on the metal parts, and also serves as a guide for the nylon skirted pistons, thereby eliminating a separate piston guide sleeve commonly found in previous designs.

The use of the parallel intake and discharge passages at the top of the casing with the intake and discharge ports in a handy location at the top of the casing permits easy mounting of the pump in difiicult locations and also affords extremely easy connections for the fluid lines leading to and from the pump. This is an especially handy arrangement where the pump is mounted on the top of the liquid tank for a portable or mobile spraying apparatus,

With reference to FIGURES 2 and 3 it will be seen that one end of the crankshaft projects out of the casing farther than the other end and the projecting end is provided with a key way 51. With this simple arrangement, the pump shaft may be connected directly to and powered by, an internal combustion engine or an electrical engine, may be provided with a pulley or sprocket for a belt or chain drive, or may be connected directly to the power take-off shaft of a power vehicle such as a tractor by means of an ordinary adaptor. This gives a range of ready connections for the driving of the pump and no individual design for each driving connection is necessary, as was commonly provided in the past.

The provision of a structure whereby a fiat composition gasket may be used on each side of the respective valve plate eliminates costly machining of the pump body, as would be required by the use of an O-ring around individual recessed valves, and permits the use of simple cored holes in the casting or casing to provide sufiicient clearance for the valve cages. For examination or attention, the valves are readily accessible by the simple expedient of removing the casing head, no special tool other than an ordinary wrench being required. It will also be noted that attention may readily be given the valves since each valve and its spring, when compressed, are readily removable and replaceable through the side openings in the skeleton valve cages, and thus the poppet valves may be replaced in the field with extremely little effort.

The small size and compact shape of the pump, the simplicity of the operating parts and the ease with which a the pump may be dismantled and assembled all contribute to a highly efiicient, high capacity, lightweight pump requiring little attention and when attention is required it may be provided with little effort and loss of time.

It will be understood that modifications and variations may be effected without departing from the scope of the novel concepts of the present invention.

I claim as my invention:

1. In a pump, a casing of the general shape of a rectangular prism having a transverse opening therethrough with a pair of opposed cylinders in communication with said opening and opposite ends of the casing, said casing also having spaced parallel intake and discharge passages extending from end to end of the casing above said opening and ports to said passages through the top of the casing, identical covers and bearing assemblies closing said transverse opening at each side of said casing, a

crankshaft extending through said bearing assemblies, opposed pistons in said cylinders and connected to said crankshaft for joint operation thereby, identical valve plates over each end of said casing each having an aperture opposite the respective cylinder and an aperture opposite the opening of each said passage, a poppet valve carried by each said plate for each said passage opening to admit liquid through the intake passage and permit outflow through the discharge passage, identical cup-shaped casing heads secured over said valve plates, and a flat gasket on each side of each valve plate to effect a seal between the casing and plate and between the plate and head.

2. In a pump, a casing of the general shape of a rectangular prism having a transverse opening therethrough with a pair of opposed cylinders in communication With said opening and opposite ends of the casing, said casing also having spaced parallel intake and discharge passages extending from end to end of the casing above said opening and ports to said passages through the top of the casing, identical covers and bearing assemblies closing said transverse opening at each side of said casing, a crankshaft extending through said bearing assemblies, opposed pistons in said cylinders and connected to said crankshaft for joint operation thereby, identical valve plates over each end of said casing each having an aperture opposite the respective cylinder and an aperture opposite the opening of each said passage, a poppet valve carried by each said plate for each said passage opening to admit liquid through the intake passage and permit outflow through the discharge passage, identical cupshaped casing heads secured over said valve plates, a flat gasket on each side of each valve plate to effect a seal between the casing and plate and between the plate and head, and a porcelain lined metal sleeve in each said cylinder held in place by the respective valve plate.

3. In a pump, a casing of the general shape of a rectangular prism having a transverse opening therethrough with a pair of opposed cylinders in communication with said opening and opposite ends of the casing, said casing also having spaced parallel intake and discharge passages extending from end to end of the casing above said opening and ports to said passages through the top of the casing, identical covers and bearing assemblies closing said transverse opening at each side of said casing, a crankshaft extending through said bearing assemblies, opposed pistons in said cylinders and connected to said crankshaft for joint operation thereby, identical valve plates over each end of said casing each having an aperture opposite the respective cylinder and an aperture opposite the opening of each said passage, a poppet valve carried by each said plate for each said passage opening to admit liquid through the intake passage and permit outflow through the discharge passage, identical cupshaped casing heads secured over said valve plates, a flat gasket on each side of each valve plate to effect a seal between the casing and plate and between the plate and head, a porcelain lined metal sleeve in each said cylinder held in place by the respective valve plate, and a plastic skirt on each said piston, said porcelain lined sleeve forming the only guide means for the piston skirt.

4. In a pump, a casing having opposed cylinders open at opposite ends of the casing, said casing also having spaced intake and discharge passages open at each end of the casing and ported through the casing between the ends of the passages, pumping means in said casing acting through said cylinders, a stainless steel valve plate over each end of said casing having a port opposite the respective cylinder and ports opposite the ends of said passages, a skeleton valve cage secured to the outer face of each said plate over one of said passage ports, a spring biased poppet valve in said cage, a similar cage and valve on the inner face of each said plate over the other passage port, and a cup-shaped casing head over each said valve plate.

5. In a pump, a casing having intake and discharge passages therein opening through an end of the casing, said casing having a cylinder also opening through the same casing end, pumping means inside said casing acting through said cylinder, a flat valve plate over said casing end .and ported opposite said cylinder and said passages, a skeleton valve cage on one face of said plate over one of the passage ports, a spring biased poppet valve in said cage, a similar cage and valve on the opposite face of said plate over the other passage port, and a cup-shaped casing head over said valve plate.

6. In a pump, a casing having intake and discharge passages therein opening through an end of the casing, said casing having a cylinder also opening through the same casing end, pumping means inside said casing acting through said cylinder, a flat valve plate over said casing end and ported opposite said cylinder and said passages, a skeleton valve cage on one face of said plate over one of the passages ports, a spring biased poppet valve in said cage, a similar cage and valve on the opposite face of said plate over the other passage port, a cupshaped casing head over said valve plate, and a lining sleeve in said cylinder held in place by said valve plate.

7. In a pump, a casing having intake and discharge passages therein opening through an end of the casing, said casing having a cylinder also opening through the same casing end, pumping means inside said casing acting through said cylinder, a flat valve plate over said casing end and ported opposite said cylinder and said passages, a skeleton valve cage on one face of said plate over one of the passage ports, a spring biased poppet valve in said cage, a similar cage and valve on the oppo site face of said plate over the other passage port, a fiat gasket on the inner side of said valve plate, a flat gasket on the outer side of said valve plate, and a cupshaped casing head secured to said end of the casing through said valve plate and said gaskets.

References Cited in the file of this patent UNITED STATES PATENTS 52,070 Parkhurst Jan. 16, 1866 187,934 Temple Feb. 27, 1877 1,377,583 Human May 10, 1921 1,719,825 Murray July 9, 1929 2,648,287 Thoren et al. Aug. 11, 1953 2,771,037 Johnston Nov. 20, 1956 2,834,298 Wright May 13, 1958 FOREIGN PATENTS 72,123 Australia July 10, 1916 142,707 Germany of 1903 

